Refrigerating apparatus



Nov. 6, 1934-. L. A. PHILIPP REFRIGERATING APPARATUS Filed April 10, 1953 INVENTOR. L4MPW0 1y. PHIL/PP fi Q A 8,

ATTORNEY.

Patented Nov. 6, 1934 UNITED STATES 1,9':9,ess nnmrcnm'mve mmws Lawrence A. Philipp, Detroit, Mich, assignor to Kelvinator. Corporation, Detroit, Mich, a cotporation of Michigan Application April 10, 1933,. Serial No. 665,271

10 Claims.

This invention relates to refrigerating apparatus, and more particularly to refrigerating apparatus of the'compression type arranged for refrigerating large quantities of foods and for freezing large quantities of substances.

One of the objects of my invention is to provide an improved refrigerating system for freezing substances and for cooling circulating air in a refrigerator cabinet. I

Another object of my invention is to provide 0 in a refrigerator cabinet a relatively large heat capacity refrigerant evaporator for freezing large quantities of substances, and arelatively small heat capacity refrigerant evaporator for cooling l5 circulating air in the food storage compartment of said cabinet, and to arrange for precooling a portion of the circulating air by the refrigerating effect of the large heat capacity evaporator and later cooling the air to the desired temperature by the small heat capacity evaporator.

Another object of my invention is toemploy forced convection means in a new and novel manner in the aforesaid refrigerating apparatus.

Another object of my invention is to provide 335 within a refrigerator cabinet an improved arrangement of and control for refrigerant evaporating means, which is arranged for operating without the collection of frost thereon or a slight film of frost is allowed to collect there- 33 on during the on-phase of the refrigerating cycle and is melted foif during the off-phase of the refrigerating cycle, while at the same time pro-' visions are made for freezing substances, such as ice cubes and the like, and for cooling circulating air in the food storage compartment where- .by continuous refrigeration at substantially constant, predetermined temperatures is insured and the necessity of periodic inoperative conditions of the system for defrosting is avoided.

Other objects and advantages will be apparent from the following description, reference being had to the accompanying drawing.

In the drawing: Fig. 1 is a front view in elevation of a refrigerating apparatus embodyingfeatures of my invention; 1

Fig. 2 is a vertical viewin cross section of the refrigerating apparatus shown in Fig. l with a diagrammatic illustration of the refrigerant 5o condensing element removed from the cabinet; and

Fig. 3 is a view taken along the lines 3-3 of Fig. l.

Referring to the drawing, numeral 20 designates, in general, a refrigerator cabinet having insulated walls, including top wall 22, bottom wall 23, side walls 24, rear wall 25 and front wall 26. The cabinet 20 is provided with food storage compartments 30 and 32.

Within the cabinet adjacent the top wall 22 and between the storage compartments 30 and.

32 there is disposed a refrigerant evaporating element 34. A metallic shield or shell 35 is arranged to cooperate with the top wall 22, rear wall 25 and a front cover plate or shield 36 to provide a low temperature compartment 37 and to isolate the evaporating element 34 from direct contact with'the circulating air in the compartments 30 and 32. A pair of vertically ex-.

tending, spaced apart baffles 38 are disposed on 7G opposite. sides of the shell 35 with their upper ends terminating below the top wall 22 of cabinet 20 and their lower ends terminating above the bottom wall 23 of the cabinet 20. The bafiies 38 extend from the rear wall 25 to a front 010- 76 sure plate 36. By so locating the bames 38, there is provided passages 41 and 42 on opposite sides of the shell.35, and a larger passage 44 is pro vided below the shell 35 between the baffles 38. rear wall 25 and the front cover plate 36. v

Within the passage 44 there is disposed a relative small heat capacity refrigerant evaporatingelement 46 which is supported by air deflectors and drip water conductors 48 which are secured on their upper ends to the baflles 38. A drip receiver 49 is positioned on the bottom wall 23 of thecabinet 20 immediately below the lowermost ends of the drip water conductors 48 to receive the drip water from the evaporating element 46.

Preferably, the refrigerant evaporating element 34 is of relatively large heat capacity for freezing large quantities of ice cubes and the like and comprises, in general, a pluraiity of ver- 1 tically spaced refrigerated shelves 50, which may be of any suitable construction. ,The shelves 50 are connected to each other by means of conduits 51. The shelves 50 are rigidly secured in positionby means of vertical metallic members 53. The shelves provide supports for ice mak- 102 ing receptacles 55. Positioned at the uppermost part of the element 34; is a refrigerant accumulator 54.

The relatively small heat capacity refrigerant evaporator 46 comprises, in general, two looped 106 refrigerant conduits 56, which are, preferably, in the form of serpentine coils. Manifolds 53 and 59 are arranged to interconnect the, inlets and outlets, respectively, of the two coils 56. In order to increase the heat transfer characteristics 110 a vapor return conduit 64. The condensing element 62 comprises, in general, a compressor 66, motor 67 for operating the compressor, a condenser 68, and a high side float mechanism 69. The compressor withdraws gaseous refrigerant from the accumulator 54, compresses the gaseous refrigerant and delivers it to the condenser 68 wherein it is liquefied and from which it is delivered to the interior of the housing of the float mechanism 69. Liquid refrigerant is supplied to the elements 46 and 34 through the supply conduit 63 under the control of float mechanism Liquid refrigerant is flrst delivered to the element 46 whence it is delivered to the evaporating element 34 after first passing through a pressure responsive valve 72. The pressure responsive valveis provided for maintaining a pressure differential between the elements 46 and 34. In view of the fact that the elements 34 and 46 are of the so called flooded type, the pressures therein will bear a direct relation to the temperatures therein. Thus, the pressure responsive valve '72 is provided for obtaining a temperature differential between said elements. The pressure responsive valve 72 may be of any suitable type, preferably of the type which includes a weighted valve proper (not shown) responsive to pressures of the refrigerant in the element 46. By this arrangement, a temperature differential is obtained between the two evaporating ele ments 34 and 46;

Preferably, the condensing element is intermittently operated. In order to control the operation of the condensing element, I have provided a thermostatically controlled switch 80. To the switch is connected a fluid containing thermostatic bulb 82 by means of conduit 84. The bulb 82 is disposed in the food storage compartment 32 so that the expansion and contraction of the fluid contained therein will be influenced by changes in temperatures in the circulating air in said compartment to thereby control the operation of the switch v80 in response to changes in temperatures of the circulating air in the cabinet 20. The switch 80 controls the motor circuit to the power mains 86.

Preferably, the thermostatic switch 80 is set so that evaporating element 46 will be operated at temperatures which are slightly above that which would be likely to cause the collection.

of frost or ice therein due to the deposit of moisture from the circulating air in the food storage compartments 30 and 32. If desired, this thermostat may be set so that the condensing element will operate sufliciently to supply refrigerant to the element 46 in such a manner that the operation of the element 46 would allow a slight film of frost to collect thereon during the on-phase of the refrigerating cycle and melt 01f during the off-phase of the refrigerating cycle. If desired, the thermostatic bulb 82 may be placed in contact with the evaporating element 46 where it will be directly responsive to changes in temperatures within the element 46.

tively small heat capacity refrigerant evaporating element, I have provided an electrically operated fan 90, which is disposed between the lowermost part of the shell 35 and the element 46 within the passage 44. By this arrangement, the air in the compartments 30 and 32 is circulated in contact with the element 46 whence it passes between the lowermdst'portions of baiiles 38 and the bottom wall 23 of cabinet 20 through the compartments 30 and 32 whence the warm air enters passages 41 and 42 where it is precooled by the refrigerating effect of the evaporating element 34. The element 34 is arranged to cool the metallic shell 35 to a temperature below the temperature of the warm air entering passages 41 and 42. The cooling of the shell 35 takes place due to the circulation of air within the shell 35, which circulating air is cooled by the element 34 and contacts with the inner walls of shell 35. The circulating air, after being precooled by the shell 35, is again passed into contact with the element 46 where it is cooled to the desired temperature and recirculated.

Preferably, the front wall 26 of the cabinet 26 is provided with separate doors 92, 93 and 94 for gaining access to the compartments 30, 3'7 and 32, respectively. Access may be had to compartment 3'7 through openings 96, which are provided in closure plate 36, to permit the insertion and removal of trays 55. The cover plate 36 is also pro-., vided with an opening 97 in the lower part thereof to permit the insertion and removal of the drip receiver 49. The opening 9'7 is closed by door 98.

From the foregoing, it will be noted that I have arranged for cooling large spaces for the storageof foods and the like by using a relatively small heat capacity refrigerant evaporator and a fan for circulating the flow of air in the cabinet over said element. It will also be noted that I have provided for freezing large quantities of ice cubes by a relatively large heat capacity refrigerant evaporator, which is isolated-from direct contact of the circulating air in the compartments 30 and 32. This avoids the collection of frost and ice on the element 34 due to the deposit of moisture thereon by the circulating air inthe compartments 30 and 32. By this arrangement, only that air which is enclosed within the compartment 37 contacts with the element 34. The amount of moisture deposited from this air is such that the element need be defrosted only after a very long period of operation. In the event it is desired to defrost the element 34, I have provided an opening 100 in the bottom wall of the shell 35 adjacent the rear wall 25 of cabinet 20 to permit the defrost water to drain into the passage 44 whence it passes into the receiver 49. Thus, it will be noted that the drip water conductors 48 serve to direct the drip water from both of the elements 34 and 46 into the receiver 49.

Although only a preferred form of the invention has been illustrated, and that form described in detail, it will be apparent to those skilled in 'the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. I

What I claim as my invention is:

1. Refrigerating apparatus comprising, in combination, a cabinet having a food storage compartment, a refrigerant evaporating element disposed in said cabinet, a metallic shield arranged for isolating said element from direct contact with the circulating air in said compartment, said shield comprising means for precooling the circulating air, and a refrigerant evaporating element located below said shield for cooling the circulating air after it has contacted with said shield.

2. Refrigerating apparatus comprising, in combination, a cabinet having a food storage compartment, a refrigerant evaporating element disposed in said cabinet, a metallic shield cooperating with a wall of said cabinet for isolating said element from direct contact with the circulating air in said cabinet, baflie means cooperating with a portion of said shield to provide a passage for circulating air, and a refrigerant evaporating element located at one endrof said passage for cooling said circulating air. i

3. Refrigerating apparatus comprising, in combination, a cabinet having a food storage compartment, a refrigerant evaporating element disposed in said cabinet, a metallic shield cooperating with a wall of said cabinet to enclose said element, a second refrigerant evaporating element disposed in said cabinet below said shield, and a fan for circulating air in said compartment, said fan being disposed between said shield and said second refrigerant evaporating element.

4. Refrigerating apparatus comprising, in combination, a cabinet having a food storage compartment, a refrigerant evaporating element disposed in said cabinet, a shield cooperating with a wall of said cabinet to enclose said element, a pair of baflles vertically arranged and spaced apart on opposite sides of said shield and having their ends spaced from the top and bottom walls of the compartment to provide passages for the circulating air in said compartment, and a refrigerant evaporating element disposed between said bafiies for cooling said circulating air.

5. Refrigerating apparatus comprising-in combination, a cabinet having a food storage compartment, a refrigerant evaporating element disposed adjacent the top of said compartment, a refrigerant evaporating element disposed below saidfirst named element, a fan disposed between said elements, a drip receiver positioned below said latter element, and means for directing the drip water from said elements to said receiver.

6. Refrigerating apparatus comprising in combination, a cabinet, a plurality of evaporators in said cabinet, one of said evaporators forming a freezing zone, another of said evaporators providing for cooling circulating air in the cabinet, a

shield for preventing circulating air from contacting with the freezing zone, said shield being spaced from the freezing zone and in heat conducting relation between the circulating air and iii; first mentioned'evaporator for precooling the '7. Refrigerating apparatus comprising in cornshield for preventing circulating air from con bination, a cabinet, a plurality of evaporator-s in said cabinet, one of said evaporator-s forming a freezing zone, another of said evaporators providing for cooling circulating air in the cabinet, a

tacting with the freezing zone, said shield being spaced from the freezing zone and in heat conducting relation between the circulating air and the first mentioned evaporator, and means for maintaining a lower temperature in the first mentioned evaporator than the second mentioned evaporator.

8. Refrigerating apparatus comprising, in combination, a cabinet, a plurality of evaporators in said cabinet, one of said evaporators forming a freezing zone, another of said evaporators providing for cooling circulating air in the cabinet, a shield for preventing circulating air from contacting with the freezing zone, said shield being spaced from the freezing zone and in heat conducting relation between the circulating air and the first mentioned evaporator, and a fan for circulating air about said cabinet and air cooling evaporator, said fan being .so positioned as to cause such forced air to contact with a surface 10a of said shield before contacting with said air cooling evaporator.

9. Refrigerating apparatus comprising, in combination, a cabinet, a plurality of evaporatorsin said cabinet, one of said evaporator-s forming a freezing zone, another of said evaporators providing for cooling circulating air in the cabinet, a shield for preventing circulating air from con-' tacting with the freezing zone, said shield being spaced from the freezing zone and in heat con-' ducting relation between the circulating air and the first mentioned evaporator, means for main-= taining a lower temperature in the first mentioned evaporator than the second mentioned evaporator, and a fan for circulating air about said cabinet, said shield and said air cooling evaporator.

l0. Refrigerating apparatus comprising, in combination, a cabinet, a plurality of evaporators in said cabinet, one ofsaid evaporators forming a freezing zone, another of said evaporators providing for cooling circulating air in the cabinet, a boxdike 'shield for preventing circulating air from contacting with the freezing zone, said shield being spaced from the freezing zone and in 1 heat-conducting relation between the circulating air and the first mentioned evaporator, and means for maintaining a lower temperature in the first mentioned evaporator than the second 

